JP2018018077A - Head-mounted display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a head-mounted display comprising a device main body and a video display device.SOLUTION: The device main body includes a first part and a second part connected to the first part. The video display device is installed at the device main body. The video display device projects a video screen onto a projection object. The video display device includes a video output element, a plurality of lens elements, a light diffusion element and an imaging element. The imaging element projects a video light flux onto the projection object to display the video screen. The lens element has a first lens element and a second lens element. The video output element generates an intermediate video between the first lens element and the second lens element on a propagation path of the video light flux. The light diffusion element is placed in a predetermined section having the intermediate video on the propagation path of the video light flux as a center.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a display device, and more particularly to a head mounted display.

  At present, the eye-eye display (NED) or the head-mounted display (HMD) is a wearable display device with great potential. The eyepiece display is divided into two types of augmented reality (Augmented Reality, AR) and virtual reality (Virtual Reality, VR) based on whether environmental images can be simultaneously viewed. Speaking of virtual reality, emphasis is placed on the sense of truth in the virtual world, that is, the wide viewing angle beyond the limit of the eyes. The demand for augmented reality is how to provide the best video quality on the premise of miniaturization and weight reduction. So far, augmented reality head-mounted displays are key to the development of optical technology, considering how to consider the four important needs of the field of view (FOV), volume, weight and appearance at the same time. is there.

  In the conventional head-mounted display architecture, the modulated illumination light beam that meets the needs of the video output element is output from the light source module. After passing through the video output element, the illumination light beam becomes a light beam having video information, that is, a video light beam. Thereafter, the image light flux further passes through one or more lens elements and / or mirror elements and an imaging element, and then enters the projection target, for example, the eyes of the user. Then, the image light beam is focused on the retina by the eye lens and imaged. Generally speaking, the image light flux projected onto the projection target has a circular area of about 1.6 to 2.0 mm in diameter (size). This means that the virtual image cannot be clearly seen unless the pupil of the user's eye is accurately positioned at the projection position of the image light flux. However, since the size of the quintet on the user's face is different, the projection position of the image light beam can be positioned in the pupils of different user's eyes by adding one set of adjusting devices. Further, in the conventional architecture in which an optical waveguide element is used for a head-mounted display, two sets of beam splitter arrays (Beam Splitter Array) are used, and the projection region of the image light flux is on two different directions (vertical direction and horizontal direction). Since it is necessary to extend the length of the head mounted display, the volume of the entire head mounted display is increased and the cost is increased.

  In addition, since this "background art" part is only for helping the understanding of the contents of the present invention, the contents disclosed in this "background art" part are not known to those skilled in the art. May include technology. Thus, the content disclosed in this “Background” section is well known to those skilled in the art prior to the filing of the present invention, or the problem to be solved by one or more embodiments of the present invention. Does not mean that

  An object of the present invention is to provide a head-mounted display that expands a user's field of view (FOV), has a small volume, is light in weight, and can provide good wearing comfort. is there.

  Other objects and advantages of the present invention can be further understood from the technical features disclosed in the present invention.

  In order to achieve one or some or all of the above objects or other objects, in one embodiment of the present invention, a head mounted display is provided, which includes an apparatus main body and an image display apparatus. The apparatus body includes a first part and a second part connected to the first part. The video display apparatus is installed in the apparatus main body. The video display device is used to project a video screen onto a projection target. The video display device includes a video output element, a plurality of lens elements, and a light diffusing element. The image light flux output from the image output element is projected onto the projection target by a virtual image method via the lens element and the light diffusing element to display the image screen. The lens element includes a first lens element and a second lens element. The image output element is located in the propagation path of the image light flux, and the image output element generates an intermediate image between the first lens element and the second lens element. The light diffusing element is installed in a predetermined section centering on the intermediate image in the propagation path of the image light flux.

  As described above, the embodiments of the present invention have at least one of the following advantages or functions / effects. That is, in the image display device according to the embodiment of the present invention, since the light diffusing element is installed in a predetermined section centering on the intermediate image in the propagation path of the image light beam, the image light beam has a large projection area on the projection target, In addition, the head mounted display can not only provide good wearing comfort, but also enlarge the user's field of view (FOV), reduce the volume of the head mounted display and reduce the weight. it can.

  To make the above features and advantages of the present invention more apparent, the following detailed description will be given by way of example and with reference to the accompanying drawings.

It is a schematic diagram which shows the head mounted display in one Example of this invention. It is a schematic diagram which shows the head mounted display in the other Example of this invention. It is a schematic diagram which shows the optical system of the video display apparatus in one Example of this invention. It is a schematic diagram which shows the optical system of the light source module in one Example of this invention. It is a schematic diagram which shows the optical system of the video display apparatus in the other Example of this invention. It is a side view which shows projection to the projection object of the image light beam in one Example of this invention. FIG. 6B is a schematic diagram showing projection of the image light beam shown in FIG. 6A up to a projection plane. FIG. 6B is a three-dimensional view showing the projection of the image light beam shown in FIG. 6A up to the projection plane. It is a side view which shows projection to the projection object of the image light beam in one Example of this invention. FIG. 7B is a schematic diagram showing projection of the image light beam shown in FIG. 7A up to a projection plane. FIG. 7B is a three-dimensional view showing the projection of the image light beam shown in FIG. 7A up to the projection plane. It is a side view which shows projection to the projection object of the image light beam in one Example of this invention. FIG. 7B is a schematic diagram showing projection of the image light beam shown in FIG. 7A up to a projection plane. FIG. 8B is a three-dimensional view showing the projection of the image light beam shown in FIG. 8A up to the projection plane. It is a side view which shows projection to the projection object of the image light beam in one Example of this invention. FIG. 9B is a schematic diagram showing projection of the image light beam shown in FIG. 9A up to a projection plane. FIG. 9B is a three-dimensional view showing projection of the image light beam shown in FIG. 9A up to a projection plane. It is a side view which shows projection to the projection object of the image light beam in one Example of this invention. FIG. 10B is a schematic diagram showing projection of the image light beam shown in FIG. 10A up to a projection plane. FIG. 10B is a three-dimensional view showing projection of the image light beam shown in FIG. It is sectional drawing of the optical waveguide element in one Example of this invention. FIG. 12 is a three-dimensional view of the optical waveguide device in the embodiment shown in FIG. FIG. 12 is a light spot diagram of a light input end of the optical waveguide device in the embodiment shown in FIG. It is a three-dimensional view showing projection of an image light beam onto an optical waveguide device in one embodiment of the present invention. FIG. 2 is a schematic diagram showing projection of a video light beam shown in FIG. 1 to a projection plane. It is a schematic diagram which shows the surface fine structure of the light-diffusion element in one Example of this invention.

  The above and other technical contents, features, functions and effects of the present invention will be clarified by the following detailed description of preferred embodiments based on the attached drawings. It should be noted that the terms for the directions mentioned in the following examples, for example, up, down, left, right, front or back, are only directions of the attached drawings. Accordingly, the directional terminology used is for the purpose of describing the present invention only and is not intended to limit the present invention.

  FIG. 1 is a schematic diagram showing a head mounted display in one embodiment of the present invention. As shown in FIG. 1, the head mounted display 100 of the present embodiment includes an apparatus main body 110 and an image display apparatus 120. The apparatus body 110 includes a first portion 112 and a second portion 114 connected to the first portion 112. In the present embodiment, the apparatus main body 110 includes, for example, glasses, but the aspect of the glasses does not limit the present invention. The first part 112 has three parts: a rim (the part that fixes the lens), a temple (a vine (a part that supports the glasses)), and a pad (a nose pad (a part that holds the nose from both sides to support the glasses)). At least one of them. In this embodiment, the rim, temple, and pad may be assembled with a fixing element such as a screw after being manufactured, for example. In one embodiment, the rim, temple, and pad may be integrally formed. In the present invention, the aspect of the apparatus main body 110 is not limited. The second portion 114 includes lenses, the number of lenses is, for example, one or more and the lenses are assembled to the rim. In other embodiments, the first portion 112 and the second portion 114 may be integrally molded, for example, an architecture such as goggle.

  In this embodiment, the video display device 120 is installed in the device main body 110. The video display device 120 is used to project a video screen onto a projection target. The projection target is, for example, the user's eyes (projection target 800 in FIG. 3). In this embodiment, the video display device 120 includes a light source module 122, a video output element 126, an imaging element 128, a plurality of lens elements 121_1, 121_2, 121_3, a mirror element 123, and a light diffusing element 127. In the present embodiment, the lens elements 121_1, 121_2, and 121_3 are installed in the propagation path of the image light beam L2, and the lens elements 121_1, 121_2, and 121_3 are installed between the image output element 126 and the imaging element 128. The mirror element 123 is installed in the propagation path of the image light beam L2, and the mirror element 123 is installed between the lens elements 121_2 and 121_3. In this embodiment, the light source module 122, the video output element 126, the lens element 121_1 (first lens element), 121_2 (second lens element), 121_3 (third lens element), the light diffusion element 127, and the mirror element 123 are Distributed to the first portion 112 of the apparatus main body 110.

  For example, the light source module 122 may be installed on a temple. The video output element 126 may be installed on the rim. The lens elements 121_1, 121_2, 121_3 and the light diffusing element 127 are dispersedly installed on the first portion 112 of the apparatus main body 110. In this embodiment, the imaging element 128 is installed in one of both the first part 112 and the second part 114 of the apparatus main body 110. For example, the imaging element 128 may be integrated into the lens of the glasses, or may be located inside the lens and where it is affixed to the lens, or the imaging element 128 may be positioned at the pad It may be installed at the position of the first portion 112 adjacent to (not shown).

  In the present embodiment, the light source module 122 is used to output the illumination light beam L1 to the video output element 126. The video output element 126 converts the illumination light beam L1 to form the video light beam L2, and the video output element 126 outputs the video light beam L2 to the lens elements 121_1, 121_2, 121_3, the light diffusion element 127, and the mirror element 123. . The image light beam L2 propagates to the imaging element 128 via the lens elements 121_1, 121_2, 121_3, the light diffusing element 127, and the mirror element 123. The imaging element 128 further displays the image screen by projecting the image light beam L2 onto the projection target by the virtual image projection method. In other words, in this embodiment, the imaging element 128 projects the image light beam L2 onto the projection target by the virtual image projection method to display the image screen. In this embodiment, the mirror element 123 is used to change the propagation path of the image light beam L2. For example, the mirror element 123 includes a reflection mirror, which is used to reflect the image light beam L2 from the lens element 121_2 to the lens element 121_3. Although the number of mirror elements 123 in this embodiment is one, the number of mirror elements 123 may be plural depending on different optical path design methods. In the present invention, the number of mirror elements 123 is not limited.

  In the present embodiment, the image output element 126 is located in the propagation path of the image light beam L2, and the image output element 126 displays an intermediate image between the lens elements 121_1 and 121_2, for example, the intermediate image M of FIG. Generate as follows. In this embodiment, the light diffusing element 127 is installed in a predetermined section centered on the intermediate image in the propagation path of the image light beam L2. In one embodiment, the light diffusing element 127 is installed, for example, at a position where the intermediate image M is generated on the propagation path of the image light beam L2. The present invention is not limited to the installation position of the light diffusing element 127 in the predetermined section.

  In the present embodiment, the environmental light beam L3 passes through the second portion 114 of the apparatus main body 110 and is projected onto the projection target, for example, so that the head mounted display 100 can provide an augmented reality function. . The distributed installation method of each element of the image display device 120 in the embodiment of the present invention can also be used for a virtual reality or mixed reality (MR) head-mounted display, that is, in the present invention, an image display is performed. The application of the device 120 is not limited.

  In the present embodiment, the video output element 126, the lens elements 121_1, 121_2, 121_3, the light diffusing element 127, and the mirror element 123 are distributed along the first portion 112 and the second portion 114. For example, in this embodiment, the distribution areas of the video output element 126, the lens elements 121_1, 121_2, 121_3, the light diffusing element 127, and the mirror element 123 are areas adjacent to the connection portion between the first portion 112 and the second portion 114. is there. In this embodiment, the color-modulated illumination light beam L 1 that meets the needs of the video output element 126 is emitted from the light source module 122. The illumination light beam L1 forms a light beam bearing video information after passing through the video output element 126, that is, a video light beam L2. After that, the image light beam L2 further passes through the lens elements 121_1 and 121_2, the light diffusing element 127, the lens element 121_3 and the mirror element 123, and the imaging element 128, and then enters the user's eyes, and the image is generated by the crystalline lens. The light beam L2 is focused on the retina to form an image (for example, a virtual image).

  The embodiment of the present invention does not limit the mode of the apparatus main body (for example, glasses). FIG. 2 is a schematic view showing a head-mounted display in another embodiment of the present invention. As shown in FIGS. 1 and 2, the head mounted display 200 of this embodiment is similar to the head mounted display 100 of the embodiment shown in FIG. 1, but the difference between the two is mainly, for example, the apparatus main body 210. It is in the aspect. For example, in the present embodiment, the first portion 212 of the apparatus main body 210 does not completely cover the edge of the second portion 214.

  In the present embodiment, the projection target is located on the reference plane, and the projection on the reference plane of the video output element 226 is located above the projection target. For example, the projection target is the eyes of the user 900, and the reference surface is the face of the user 900. In the present embodiment, the projection of the video output element 226 on the face of the user 900 is located above the eye and at a location approaching the eyebrows. In other words, the projection on the reference surface of the video output element 226 is located above the projection target. In the present embodiment, the lens elements 221_1 and 221_2 are located inside the eyes and close to the nose but away from the ears.

  In the present embodiment, for example, the light source module 222 is installed on the left side of the user 900 with the user 900 as a reference. The traveling direction of the optical path is from left to right and again to the left. In other words, the image light flux L2 propagates from the eyebrows of the user 900 to the nose and from the nose to the eyes. Further, in this embodiment, the imaging element 228 may be integrated with the lens and integrated with the lens, or may be attached to the lens inside the lens as shown in FIG. It may be located at a location.

  In addition, since the description of the embodiment shown in FIG. 1 can be referred to for the installation position and operation method of each element of the head mounted display 200 in the present embodiment, detailed description thereof is omitted here.

  FIG. 3 is a schematic diagram showing a video display device in one embodiment of the present invention. FIG. 4 is a schematic diagram showing a light source module according to an embodiment of the present invention. As shown in FIGS. 3 and 4, the video display device 300 of this embodiment includes a light source module 310, a video output element 326, a first lens element 330, a light diffusing element 370, a second lens element 340, and an imaging element 328. including. In the present embodiment, the lens module 330 is installed in the propagation path of the image light beam L2, and the lens module 330 is installed between the image output element 326 and the imaging element 328. For convenience, FIG. 3 shows only the first lens element 330, the light diffusing element 370, and the second lens element 340 between the video output element 326 and the imaging element 328. Note that this architecture does not limit the present invention. In another embodiment, one or more other optical elements are provided between the video output element 326 and the first lens element 330 and between the second lens element 340 and the second lens element 340. However, the present invention is not limited to this.

  In this embodiment, the light source module 310 includes a light emitting element 322, a lens element 312, a light propagation element 324, and a light collimation element 314. In the present embodiment, the lens element 312 is installed in the propagation path of the illumination light beam L1, and the lens element 312 is installed between the light emitting element 322 and the light propagation element 324. The light collimation element 314 is installed in the propagation path of the illumination light beam L1, and the light collimation element 314 is installed between the light propagation element 324 and the video output element 326.

  More specifically, in the present embodiment, the light emitting element 322 provides a color-converted illumination light beam L1 that meets the needs of the video output device 326, and outputs the illumination light beam L1 to the lens element 312. The lens element 312 focuses the illumination light beam L1 on the light propagation element 324. The light propagation element 324 propagates the illumination light beam L1 from the lens element 312 to the light collimation element 314. Subsequently, the light collimation element 314 collimates the illumination light beam and propagates the collimated illumination light beam L1 to the video output element 326. The video output element 326 outputs the video light beam L2 to the first lens element 330, the light diffusion element 370, and the second lens element 340 in accordance with the illumination light beam L1. The first lens element 330 collects and focuses the divergent image light beam L2 generated by the image output element 326 to form an intermediate image M. The second lens element 340 further focuses the image light beam L2 emitted from the intermediate image M on the imaging element 328. The imaging element 328 projects the image light beam L2 onto the projection target 800 and displays the image screen. The projection target 800 is, for example, a user's eyes.

  In this embodiment, the video output element 326 is located in the propagation path of the video light beam L2, and the video output element 326 generates an intermediate video M between the first lens element 330 and the second lens element 340. In the present embodiment, the light diffusing element 370 is installed in a predetermined section d centered on the intermediate image M on the propagation path of the image light beam L2. For example, depending on the design of the different first lens elements 330, the intermediate image M may be curved or flat. The light diffusing element 370 is, for example, a planar optical element, and when the distance from the optical axis center of the video output element 326 to the optical axis center of the intermediate video M is 1, the installation area is the intermediate video M This is a section that increases or decreases 10% before and after the center. Therefore, the image light beam L2 after passing through the light diffusing element 370 has its divergence angle enlarged, and the projection area collected on the projection plane EP (for example, the light spot of the image light beam L2) is also enlarged. In the present embodiment, the projection area of the image light beam L2 projected onto the projection target 800 via the light diffusing element 370 varies depending on the installation position of the light diffusing element 370 within the predetermined section d. In the present embodiment, the projected area is, for example, a transverse area projected by the image light beam L2 on the projection plane EP. The projection plane EP is, for example, a plane located at the position of the user's pupil. In one embodiment, the light diffusing element 370 is installed at the generation position of the intermediate image M on the propagation path of the image light beam L2, for example. The present invention is not limited to the installation position of the light diffusing element 370 in the predetermined section.

  In the present embodiment, the video output element 326 includes, for example, a scanning optical system, and a scanning mirror among them scans the incident illumination light beam L1 at different positions to generate a video light beam L2. In this embodiment, the scanning optical system architecture may be implemented by any scanning optical system architecture in the technical field to which the present invention belongs, but the present invention is not limited thereto. Further, the detailed architecture and implementation method thereof are obvious to those skilled in the art, and therefore detailed description thereof is omitted here.

  In the present embodiment, the lens elements included in the first lens element 330 and the second lens element 340 include, for example, a lens (Lens), a mirror (Mirror), a curved mirror (Curve Mirror), a prism (Prism), and a mirror prism (Mirror). -Prism), mirror lens (Mirror-Lens), prism lens (Pirsm-Lens), freeform lens / mirror (freeform lens / mirror) or Fresnel lens (Fresnel Lens), etc. is there. The present invention does not limit the types of the lens element 312 and the lens module 330.

  In this embodiment, the light propagating element 324 is an element such as a waveguide, an optical fiber, an integral rod, or a light pipe. The invention does not limit the type of the light propagation element 324. In this embodiment, at least the light collimation element 314 is provided between the optical fiber 324 and the video output element 326 in order to match the light distribution of the illumination light beam L1 output from the light propagation element 324 with the needs of the video output element 326. Is installed so as to adjust the light distribution in which the illumination light beam L1 enters the video output element 326. The light collimation element 314 may be, for example, a Fresnel lens, a liquid crystal lens, or a GRIN lens (GRINent Reflective Index Lens; GRIN Lens). Note that the present invention does not limit the type of the light collimation element 314.

  In the present embodiment, the imaging element 328 is used to change the traveling direction of the image light beam L2 received from the lens module 330, thereby propagating the image light beam L2 to the projection target 800, and the environment light beam L3. The user can also see the image of the environment because it is not completely shielded. In the present embodiment, the imaging element 328 includes, for example, a transflective optical element, a curved half-mirror, a liquid crystal lens, a diffraction component, a holographic element ( An optical element such as a holography component or a Fresnel lens. Note that the present invention does not limit the type of the imaging element 328.

  In this embodiment, the installation method of the video display device 300 on the corresponding device main body is, for example, the head mounted display 100 or 200 shown in FIG. 1 or FIG. For example, as shown in FIG. 1 or FIG. 2, the light source module 310 is installed at the temple of the glasses. In the present invention, the installation position of the light source module 310 is not limited. In one embodiment, depending on actual needs, the light source module 310 may be installed on a rim or other suitable location. In addition, since the installation positions and operation methods of the elements of the video display device 300 in this embodiment can be referred to the embodiments shown in FIGS. 1 and 2, detailed description thereof is omitted here.

  FIG. 5 is a schematic diagram showing a video display device in another embodiment of the present invention. As shown in FIGS. 3 and 5, the head mounted display 400 of this embodiment is similar to the head mounted display 300 of the embodiment shown in FIG. 3, but the difference between the two is mainly, for example, a light diffusing element. There are 470 installation positions. In the present embodiment, the light diffusing element 470 is installed at the generation position of the intermediate image M on the propagation path of the image light beam L2. In this embodiment, the video display device 400 includes a light source module 410, a video output element 426, a first lens element 430, a light diffusing element 470, a second lens element 440, and an imaging element 428. The video display device 400 is used to display the video screen by projecting the video light beam L2 onto the projection target 700 via the light diffusing element 470. The projection target 700 is, for example, a user's eyes. Therefore, the projection area of the image light beam L2 on the projection target 700 is large.

  In addition, the installation positions and operation methods of the elements of the video display device 400 in the present embodiment can be referred to the embodiments shown in FIG. 1 to FIG.

  In the embodiment of the present invention, the projection area of the image light flux projected onto the projection target via the light diffusing element varies depending on the installation position of the light diffusing element in the predetermined section. Further, the projection light shape in the projection target of the image light flux is determined by the shape of the light diffusing element.

  FIG. 6A is a side view showing projection of an image light beam to a projection target in a related example of the present invention. FIG. 6B is a schematic diagram showing projection of the image light flux up to the projection plane of FIG. 6A. FIG. 6C is a three-dimensional view showing the projection of the image light flux of FIG. 6A up to the projection plane. As shown in FIGS. 6A to 6C, the image light beam L2 in this related example propagates directly from the generation position of the intermediate image M to the second lens element 540 without being affected by the light diffusing element, for example. In this related example, the image light beam L2 is projected onto the projection plane EP, and the projection area is a size (size) corresponding to a circular area having a diameter of about 0.9 mm, for example.

  FIG. 7A is a side view showing projection of an image light beam to a projection target in one embodiment of the present invention. FIG. 7B is a schematic diagram showing projection of the image light flux of FIG. 7A up to the projection plane. FIG. 7C is a three-dimensional view showing the projection of the image light flux of FIG. 7A to the projection plane. As shown in FIGS. 7A to 7C, the image light beam L2 of this embodiment is propagated to the second lens element 640 after receiving the action of the light diffusing element 670, for example. In the present embodiment, the image light beam L2 is projected onto the projection plane EP, and the projection area is a size (size) corresponding to a circular area having a diameter of about 3 mm, for example. In the present embodiment, since the cross-sectional shape of the light diffusing element 670 is circular, the projection light shape on the projection target of the image light beam L2 is determined by the shape of the light diffusing element 670, and is substantially equal to that of the light diffusing element 670. It matches the shape, i.e. it is circular. In the present embodiment, taking FIG. 3 as an example, the light diffusing element 670 is installed in, for example, the predetermined section d with the intermediate image M as the center.

  FIG. 8A is a side view showing projection of a video light beam to a projection target in another embodiment of the present invention. FIG. 8B is a schematic diagram showing projection of the image light flux of FIG. 8A up to the projection plane. FIG. 8C is a three-dimensional view showing the projection of the image light flux of FIG. 8A up to the projection plane. As shown in FIGS. 8A to 8C, the image light beam L2 of this embodiment is propagated to the second lens element 740 after receiving the action of the light diffusing element 770, for example. In the present embodiment, the image light beam L2 is projected onto the projection plane EP, and the projection area is a size (size) corresponding to a circular area having a diameter of about 5 mm, for example. In the present embodiment, since the shape of the light diffusing element 770 is circular, the projection light shape on the projection target of the image light beam L2 is determined by the shape of the light diffusing element 770, and substantially the light diffusing element 770 It matches the shape, i.e. it is circular. In the present embodiment, taking FIG. 3 as an example, the light diffusing element 770 is installed in, for example, the predetermined section d with the intermediate image M as the center.

  FIG. 9A is a side view showing projection of a video light beam to a projection target in another embodiment of the present invention. FIG. 9B is a schematic diagram showing projection of the image light flux up to the projection plane of FIG. 9A. FIG. 9C is a three-dimensional view showing projection of the image light flux of FIG. 9A to the projection plane. As shown in FIGS. 9A to 9C, the image light beam L2 of this embodiment propagates to the second lens element 840 after receiving the action of the light diffusing element 870, for example. In this embodiment, the image light beam L2 is projected onto the projection plane EP, and when the projection area is an ellipse as an example, the size (size) corresponding to an ellipse area having a major axis of about 5 mm and a minor axis of 3 mm. It is. In the present embodiment, since the shape of the light diffusing element 870 is an ellipse, the projection light shape on the projection target of the image light beam L2 is determined by the shape of the light diffusing element 870, and substantially the light diffusing element 870. That is, the shape is oval. In the present embodiment, taking FIG. 3 as an example, the light diffusing element 870 is installed in, for example, the predetermined section d with the intermediate image M as the center.

  FIG. 10A is a side view showing projection of a video light beam to a projection target in another embodiment of the present invention. FIG. 10B is a schematic diagram showing projection of the image light flux of FIG. 10A to the projection plane. FIG. 10C is a three-dimensional view showing the projection of the image light flux of FIG. 10A to the projection plane. As shown in FIGS. 10A to 10C, the image light beam L2 of this embodiment is propagated to the second lens element 940 after receiving the action of the light diffusing element 970, for example. In this embodiment, the image light beam L2 is projected onto the projection plane EP, and when the projection area is an ellipse, the major axis is about 4 mm and the minor axis is about 2.5 mm corresponding to an elliptical area (about 2.5 mm). Size). In the present embodiment, since the shape of the light diffusing element 970 is an ellipse, the projection light shape on the projection target of the image light beam L2 is determined by the shape of the light diffusing element 970, and substantially the light diffusing element 970. That is, the shape is oval. In the present embodiment, taking FIG. 3 as an example, the light diffusing element 970 is installed in, for example, the predetermined section d with the intermediate image M as the center.

  In the embodiment shown in FIG. 2, the imaging element 228 may be integrated into the lens and integrally coupled with the lens, or as shown in FIG. 1, inside the lens and attached to the lens. However, the present invention is not limited to this. In one embodiment, the image display device may not include an imaging element. In this case, the image display device receives the image light beam L2 from the light diffusing element using the optical waveguide element, and the image light beam is transmitted by the optical waveguide element. L2 may be projected onto the eyes of the user 900 (another projection target). The optical waveguide element is, for example, part or all of a lens.

  FIG. 11 is a cross-sectional view of an optical waveguide device in one embodiment of the present invention. 12 is a three-dimensional view of the optical waveguide device of the embodiment shown in FIG. FIG. 13 is a light spot diagram of the light input end of the optical waveguide device of the embodiment shown in FIG. As shown in FIG. 11 to FIG. 13, the image light beam L2 of this embodiment includes, for example, a lens element (for example, the lens elements 221_1, 221_2, and 221_3 in FIG. 2) and a light diffusing element (for example, the light diffusing element in FIG. 2). 227) to the optical waveguide device 1000. The optical waveguide element 1000 projects the image light beam L2 in the projection target EB, for example, the eyes of the user 900 by the virtual image method. In this embodiment, the optical waveguide element 1000 can expand the projection area that the image light beam L2 projects onto the projection target EB by adjusting the projection light shape (that is, the light spot) of the image light beam L2.

  Specifically, in this embodiment, the optical waveguide element 1000 includes a waveguide portion 1100 and an imaging portion 1200. The waveguide 1100 receives the image light beam L2. The waveguide 1100 includes an optical input end S1 and an optical output end S2. The light input end S1 includes, for example, a light input surface, and the image light beam L2 is input from the light input surface of the light input end S1 to the waveguide unit 1100 of the optical waveguide device 1000. The light output end S2 is, for example, a connection surface between the waveguide unit 1100 and the imaging unit 1200. The image light beam L2 is output from the waveguide unit 1100 via the output end S2, and enters the imaging unit 1200. In this embodiment, the light propagation medium of the waveguide 1100 is continuously distributed from the light input end S1 to the light output end S2, and the light input end S1 and the light output end S2 are respectively the waveguide portions. The image light beam L2 that is located on both opposite sides of 1100 and enters the waveguide unit 1100 from the optical input end S1 is totally reflected in the waveguide unit 1100 and propagates to the optical output end S2. In this embodiment, the light input surface of the light input end S1 of the waveguide 1100 is rectangular, and the projected light shape of the image light beam L2 at the light input end S1 is an ellipse, as shown in FIG. is there. Among them, the light propagation medium of the waveguide 1100 is, for example, glass (optical glass, for example, quartz glass or BK7 glass), plastic material (for example, PMMA, PC, acrylic resin, APP resin, styrene resin including AS resin, etc.) ).

  In this embodiment, the waveguide unit 1100 can adjust the projection light shape in the first direction Z on the projection target EB of the image light beam L2, for example, the first light beam on the projection target EB of the image light beam L2. The length of the projection beam in the direction Z can be increased. The imaging unit 1200 includes a beam splitter array. The beam splitter array includes a plurality of beam splitters BS1 to BS8 arranged in the second direction X and installed in parallel to each other, and each of the beam splitters BS1 to BS8 transmits part of light and part of light. May be an optical element that allows reflection of light, for example, a beam splitter, so that the image light beam L2 from the waveguide 1100 can be projected onto the projection target EB by a virtual image method. Note that the number and arrangement of the beam splitters BS1 to BS8 do not limit the present invention. In the present embodiment, the imaging unit 1200 can adjust the projection light shape in the second direction X on the projection target EB of the image light beam L2, for example, the second light beam on the projection target EB of the image light beam L2. The length of the projection beam in direction X can be increased.

  In the present embodiment, the thickness WT of the imaging unit 1200 is 1.95 mm, and the distance ER between the imaging unit 1200 and the projection target EB is 15 mm. The projection target EB is rectangular, and its length and width are 10 mm and 8 mm, respectively. The field of view Φ of the user 900 is 60 degrees. The light input surface of the light input end S1 is rectangular, and its length and width are 13 mm and 3.63 mm, respectively. The various optical parameters or structural parameters described above are merely examples and do not limit the present invention. In this embodiment, the light propagation medium of the waveguide 1100 is continuously distributed from the light input end S1 to the light output end S2, and the waveguide 1100 does not include a beam splitter, and the image light beam L2 The length of the projection light shape in the first direction Z on the projection target EB can be increased. Therefore, such a design can simplify the architecture of the optical waveguide device 1000 and reduce the manufacturing cost of the optical waveguide device 1000. In addition, compared with the waveguide in the prior art including the beam splitter, the waveguide of the present embodiment does not include the beam splitter, and can increase the field of view Φ of the user 900 of the projection target EB. The size (size) is not limited by the beam splitter.

  FIG. 14 is a three-dimensional view showing the projection of the image light beam to the optical waveguide element in one embodiment of the present invention. FIG. 15 is a schematic diagram showing the projection of the image light beam up to the projection plane shown in FIG. As shown in FIGS. 11 to 15, the image light beam L2 of this embodiment is propagated to the mirror element 1428 via the second lens element 1440 after receiving the action of the light diffusing element 1470, for example. In the present embodiment, the image light beam L2 is reflected by the mirror element 1428 and then projected onto the projection plane EP (projection target). In this embodiment, some elements of the image display device that generates the image light flux L2 are the same as the arrangement positions of some elements of the image display device in the above embodiment, but the difference is in this embodiment. The imaging element is not disposed, and the image light beam L2 from the light diffusing element 1470 is propagated to the optical waveguide element 1000 using the mirror element 1428, and the optical waveguide element 1000 in this embodiment is a projection target in the above embodiment. For example, the light input surface of the light input end S1 is located on the projection plane EP. Subsequently, the optical waveguide device 1000 projects the image light beam L2 input from the light input end S1 onto another projection target EB. The eyes of the user 900 are located on the projection target EB, for example, and can receive a relatively large amount of image light beam L2. In one embodiment, the image display device does not include the mirror element 1428, and may receive the image light beam L2 from the second lens element 1440 using the optical waveguide element 1000. Project L2 into the eyes of user 900. In addition, the environmental luminous flux can pass through the imaging unit 1200 of the optical waveguide element 1000 and be projected onto the other projection target EB, so that the user can simultaneously observe the background environment and the video luminous flux L2. You can see the generated virtual image.

  In this embodiment, the light diffusing element 1470 adjusts the projection light shape of the image light beam L2 input to the light input end S1 of the optical waveguide element 1000 so as to match the shape of the light input surface of the light input end S1. be able to. For example, the light input surface of the waveguide unit of the present embodiment is rectangular, and the light diffusing element 1470 adjusts the projected light shape at the light input end S1 of the image light beam L2 to an ellipse, that is, the light diffusing element 1470. Can enlarge the projection light shape of the image light beam L2 on the projection target EB in the first direction Z as shown in FIGS. 12, 13, and 15. FIG. FIG. 15 shows a projection light shape in which the image light beam L2 is projected onto the projection plane EP (ie, the light input surface), which is elliptical and matches the rectangular light input surface. In this embodiment, the light diffusing element 1470 is installed in a predetermined section on the propagation path of the image light beam L2 and centered on the intermediate image M, whereby the projection light of the image light beam L2 input to the light input end S1. By adjusting the shape to match the shape of the light input surface, the optical efficiency of the system can be improved. Compared with a conventional architecture in which an optical waveguide element is used for a head-mounted display, the display device of the present invention uses only one set of beam splitter arrays, thereby allowing the projection light shape of the image light beam L2 to be projected in the first direction Z and the second direction. The length in the two directions X can be increased, and the projection area projected by the image light beam L2 onto the projection target EB can be enlarged.

  FIG. 16 is a schematic diagram showing the surface microstructure of the light diffusing element in one embodiment of the present invention. As shown in FIG. 16, in this embodiment, taking the light diffusing element 1470 as an example, the surface microstructure is, for example, a plurality of microstructure units (reference numerals) arranged in one direction and extending in the other direction. Not included). The light diffusing element 1470 having such a fine structure can adjust the projection light shape of the image light beam L2 input to the input end S1 so as to match the shape of the light input surface. Therefore, in the present embodiment, the projection light shape on the projection target of the image light beam L2 is determined by the design of the fine structure of the light diffusing element 1470. Note that the fine structure of the light diffusing element 1470 is merely an example, and does not limit the present invention.

In summary, the embodiments of the present invention have at least one of the following advantages or effects / functions. That is, in the image display device according to the embodiment of the present invention, the image light flux projected onto the projection target via the light diffusing element has a projection area larger than 19.6 mm ² . The head-mounted display does not require an additional adjustment system to adjust the projection position. This makes it possible to reduce the weight of the head-mounted display itself, and also allows the user to adjust the projection position after mounting the head-mounted display. There is no need to adjust, thereby improving the convenience of use of the head mounted display. In addition, the video display apparatus according to the embodiment of the present invention can enlarge the user's field of view (FOV) and reduce the size and weight of the head mounted display.

  In addition, the optical elements of the video display device are distributed in the apparatus main body. Such an arrangement method can not only improve the narrow space due to the concentrated arrangement of the optical elements on the apparatus main body, but also can share the weight to different parts of the user. Therefore, the weight distribution of the head mounted display is uniform, and good wearing comfort can be provided. In addition, since the imaging element is integrated into the lens of the glasses or attached to the lens inside the lens, the appearance of the head-mounted display can be degraded, and suddenness and discomfort can be greatly suppressed. In addition, a head-mounted display using an optical waveguide element can expand the projected area projected by the image light beam onto the projection target by arranging only one set of beam splitter arrays. Can be simplified and the cost of the head mounted display can be reduced.

  Although the present invention has been disclosed above based on the preferred embodiments described above, the preferred embodiments described above are not intended to limit the present invention, and those skilled in the art will understand the spirit of the present invention. As long as the scope of the present invention is not deviated, minor modifications and color changes can be made to the present invention. Therefore, the protection scope of the present invention is based on what is defined in the appended claims. In addition, any embodiment or claim of the present invention need not achieve all of the objects, advantages or features disclosed in the present invention. Moreover, a part of summary and the title of an invention are only for assisting the search of literature, and do not limit the scope of rights of the present invention. Also, terms such as “first”, “second”, etc. in this specification or in the claims are used to name elements or to distinguish different embodiments or ranges. Are not intended to limit the upper or lower limit on the quantity of elements.

100, 200: Head mounted display
110, 210: Main unit
112, 212: First part
114, 214: Second part
120, 220, 300, 400: Video display device
121_1, 121_2, 121_3, 221_1, 221_2, 221_3: Lens elements
122, 222, 310, 410: Light source module
123, 223, 1428: Mirror element
126, 226, 326, 426: Video output element
127, 227, 370, 470, 670, 770, 870, 970, 1470: Light diffusing element
128, 228, 328, 428, 528, 628, 728, 828, 928: Imaging element
312: Lens element
314: Optical collimation element
322: Light emitting element
324: Light propagation element
330, 430: First lens element
340, 440, 540, 640, 740, 840, 940, 1440: Second lens element
700, 800, EB: Projection target
900: User
L1: Light flux
L2: Image luminous flux
L3: Environmental luminous flux
d: Predetermined section
EP: Projection plane
M: Intermediate video
1000: Optical waveguide element
1100: Waveguide section
1200: Imaging part
S1: Optical input end
S2: Optical output end
WT: imaging area thickness
ER: Distance between the imaging unit and the projection target
BS1 to BS8: Beam splitter
X, Y, Z: Direction Φ: Field of view

Claims (18)

A head mounted display,
An apparatus main body including a first part and a second part connected to the first part; and an image display device installed in the apparatus main body for projecting an image screen onto a projection target,
The video display device includes a video output element, a plurality of lens elements and a light diffusing element,
The image light beam output from the image output element is projected onto the projection target by a virtual image projection method via the plurality of lens elements and the light diffusing element, and the image screen is displayed.
The plurality of lens elements includes a first lens element and a second lens element,
The image output element generates an intermediate image on a propagation path of the image light flux and between the first lens element and the second lens element;
The said light-diffusion element is a head mounted display installed in the predetermined area centering on the said intermediate image on the propagation path | route of the said image light beam. The head mounted display according to claim 1,
The said light-diffusion element is a head mounted display installed in the production | generation position of the said intermediate | middle image on the propagation path of the said image light beam. The head mounted display according to claim 2,
The plurality of lens elements and the light diffusing element are installed in the first part of the apparatus main body. The head mounted display according to claim 1,
The head mounted display, wherein the image light beam projected onto the projection target via the light diffusing element has a projected area larger than 19.6 mm ² . The head mounted display according to claim 1,
The head mounted display, wherein the projection light shape of the image light beam on the projection target is determined by the fine structure of the light diffusing element. The head mounted display according to claim 1,
The video output element is a head mounted display including a scanning optical system. The head mounted display according to claim 1,
The video display device further includes a light source module,
The light source module outputs an illumination light beam to the video output element,
The image light beam output from the image output element based on the illumination light beam is projected onto the projection target via the plurality of lens elements and the light diffusing element,
The light source module is a head mounted display installed in the first portion of the apparatus main body. The head mounted display according to claim 1,
The video display device further includes an imaging element,
The image light flux propagates to the imaging element via the plurality of lens elements and the light diffusing element,
The imaging element is a head-mounted display that displays the video screen by projecting the video light beam onto the projection target by a virtual image method. The head mounted display according to claim 8,
The imaging element is a head mounted display installed in one of both the first part and the second part of the apparatus main body. The head mounted display according to claim 1,
A head mounted display in which an environmental light beam is transmitted through the second part of the apparatus main body and projected onto the projection target. The head mounted display according to claim 1,
The apparatus main body includes glasses, the second portion includes a lens, and the first portion includes at least one of a rim, a temple, and a pad. The head mounted display according to claim 1,
The second portion of the device body includes at least one optical waveguide element;
The at least one optical waveguide element is installed at a position of the projection target;
The image light flux propagates to the at least one optical waveguide element via the plurality of lens elements and the light diffusing element,
The at least one optical waveguide element that receives the image light beam projects the image light beam to another projection target in a virtual image system,
The head mounted display, wherein the at least one optical waveguide element adjusts a projection light shape of the image light beam and expands a projection area onto which the image light beam is projected onto the other projection target. The head mounted display according to claim 12,
The at least one optical waveguide element includes a waveguide;
The wave guide unit receives the image light beam and adjusts a projection light shape in a first direction on the other projection target of the image light beam. The head mounted display according to claim 13,
The waveguide unit includes an optical input end and an optical output end,
The image light flux is input from the light input end to the waveguide, and is output from the light output end of the waveguide.
The head mounted display, wherein the light propagation medium of the waveguide section is continuously distributed from the light input end to the light output end. The head mounted display according to claim 13,
The optical waveguide element further includes an imaging portion,
The image light flux input from the at least one optical waveguide element propagates to the imaging unit,
The imaging unit is a head mounted display that adjusts a projection light shape in a second direction on the other projection target of the image light beam. The head mounted display according to claim 15,
The imaging unit includes a beam splitter array,
The beam splitter array includes a plurality of beam splitters arranged along the second direction and installed in parallel to each other. The head mounted display according to claim 13,
The light input end of the waveguide includes a light input surface;
The light input surface is installed at the position of the projection target,
The light diffusing element is a head mounted display that adjusts a projection light shape of the image light flux input to the light input surface so as to match a shape of the light input surface. The head mounted display according to claim 17,
The light input surface of the waveguide is rectangular,
The light diffusing element is a head mounted display that adjusts a projected light shape of the image light flux on the light input surface to an elliptical shape.

Images